Field of the Invention
The present disclosure relates to a light emitting diode (LED) lamp and in particular relates to an LED tubular lamp having a curved body.
Description of the Related Art
Curved LED tubular lamps are widely used to replace conventional incandescent lamps in the market because of their advantages including long life-time, small size and power saving. All plastic tube is a common design in conventional curved LED tubular lamps, but it may suffer from poor heat dissipation. To address the above-mentioned shortcomings associated with conventional curved LED tubular lamps, a heat-dissipation housing made of a combination of aluminum alloy and plastic cover may be used, and the light source of the curved LED tubular lamp consisting of an LED array having a plurality of LEDs welded on a circuit board may be provided on the heat dissipation housing. As disclosed in FIG. 12 of US patent publication no. 2015/0223301A1, the illustrated driver-less LED lighting device is a curved LED tubular lamp. Each of the two LED arrays 301 are provided on one of the two prongs. Each LED array 301 is provided on a PCB board 302, which itself is provided on top of the heat-sink 303 which also functions as a housing to the prong. Each prong also has a lens cover 304. There is one curved plastic connector 305a (top) and 305b (bottom) on one end to connect two prongs. There is a pin-socket assembly 306 that has two pairs of G13 bi-pin for inserting into the G-13 socket of a curved tube fixture. However, this kind of design may be prone to cause electrical shock because of conductive material, e.g., aluminum alloy, contained in the heat-dissipation housing and poor light transmittance of either the plastic cover or the plastic tube may also reduce the luminous efficiency. In addition, a dark zone (i.e., non-emitting segment having no LEDs disposed therein) may appear in the region of the plastic connector of the curved LED tubular lamp since there is no LED array disposed therein.
In addition, the light boards of the conventional curved LED tubular lamps are usually made of rigid printed circuit board (PCB), which is hard to be stretched. Therefore, a rigid board without an LED formed thereon or a wiring is placed in the connecting bar connecting two straight tube of the curved LED tubular lamp. This may result in a dark zone existing in the connecting bar of the curved LED tubular lamp. In addition, the heat dissipation rate of the rigid PCB is poor, so a heat sink structure placed outside the LED tubular lamp may be necessary. The additional heat sink will enhance the cost of the LED tubular lamp. Moreover, the rigid PCB or wire placed in the connecting bar may be easily shaken, moved, or broken due to lack of suitable positioning and guiding structures, which may affect the luminous efficiency of the curved LED tubular lamps. To address the above-mentioned shortcomings, the rigid PCBs may be replaced with flexible light boards to avoid the problem of a dark zone existing in the connecting bar of the curved LED tubular lamp. However, the flexible light board may be easily warped in the connecting bar of the curved LED tubular lamp, and the warpage may also affect the light efficiency of the LED tubular lamp. Therefore, to address the above-mentioned shortcomings associated with conventional curved LED tubular lamps, a novel curved LED tubular lamp is provided.